The present invention relates to a connecting device and, in particular, to a connecting device for interconnecting frame members of a modular construction.
Modular frame constructions are known which use extruded groove frame members to be interconnected via connection members received in T-shaped grooves in the faces of the frame members. Such frame members can be interconnected to form all manner of structures including showcases, bookcases, tables, display booths as well as one or two story offices, mezzanines and housing. Typical such frame members are disclosed in U.S. Pat. No. 3,513,606 to Jones, issued May 26, 1970 and in U.S. Pat. No. 4,490,064 to Ducharme, issued Dec. 25, 1984. The frame members have channels extending along their faces with T-shaped slots received in the faces and adapted to receive and secure fasteners behind shoulders formed in the T-shaped slots. A variety of coupling mechanisms are known. Ducharme teaches one known coupling mechanism which suffers, amongst other things, a disadvantage that the head of the fastener must be inserted into a channelway at the end of a frame member and slid longitudinally to a desired position.
U.S. Pat. No. 3,537,736 to Kroopp, issued Nov. 3, 1970 and U.S. Pat. No. 3,672,710 to Kroopp, issued Jun. 27, 1972 show mechanisms in which, amongst other things, the head of the fastener has a head with a T-shaped configuration and a different width in one direction than in another direction. Such fasteners are adapted to be inserted into the slot from the side of a frame member at any position along the frame where it may be desired to be coupled by orienting the head so that its width permits passage into the slot in the frame. After insertion, the fastener head is then rotated so that shoulders on the T-shaped head bears on shoulders in the T-shaped slot. Parallelogram shaped rotatable nuts and fasteners which can be inserted along the length of the frame members are known as shown, for example, in Jones as well as U.S. Pat. No. 3,250,584 to Tassell, issued May 10, 1966.
Coupling devices such as taught by Kroopp suffer the disadvantage that the coupling device must be manipulated by a user so as to rotate the coupling device from a lesser width position in which its T-shaped head may pass into the slot to a position in which a wider width engages shoulders within the slot. A disadvantage arises when attempting to either insert the coupling mechanism into the slot or to remove it, that it is necessary for some substantial manipulation to permit application and/or removal. Difficulties are particularly experienced during the step of removal. The present inventor has appreciated the disadvantage of having to determine the relative rotational position into which to rotate and manipulate one frame member in order to be able to couple or uncouple the same to another frame member. Manipulation may not be possible or at least may be difficult and can significantly increase the time required to apply or remove any frame member. As well, space constraints may be such that it will be very difficult to rotate or manipulate any frame member to be applied or removed.
To at least partially overcome these disadvantages of the prior art, the present invention provides a connecting device in which a T-headed bolt member is biased to assume a configuration in which it is ready for insertion into or removal from a T-shaped slot of a frame member and in which, by use of an activator in movement of the T-shaped bolt member to a locked position, the bolt member is automatically rotated to assume a position in which the head of T-shaped bolt engages shoulders of a T-shaped slot in the frame member.
It is an object of the present invention to provide a coupling mechanism which provides for a simpler coupling and uncoupling of frame members.
It is another object of the present invention to provide a connecting device in which a frame member does not need to be rotated or otherwise manipulated from a position it is desired to assume in order to permit coupling and uncoupling of the frame member.
It is another object to provide a connecting device for connecting frames having T-shaped slots in their faces in which a threaded set screw may be rotated and thereby a T-headed bolt is caused to be moved between an unlocked position in which the T-headed bolt is adapted to pass into or out of an opening to a shouldered T-shaped slot and a locked position in which the T-shaped bolt member is rotated such that within the T-shaped slot, it engages the shoulders of the slot and the T-shaped bolt member is drawn into engagement therewith.
Accordingly, in one aspect, the present invention provides a connection device comprising a hook member and a casing member,
the hook member being elongated about an axis and having a slide portion on an inner end and a hook portion on an outer end,
the casing member having a slide bore in which the slide portion of the hook member is slidably received for sliding inwardly and outwardly parallel the axis with the hook portion extending out of the slide bore and with the hook member rotatable relative the casing member about the axis,
a spring coupled between the hook member and the casing member to bias the hook member axially outwardly from the slide bore and to bias the hook member to rotate in one direction relative the casing member about the axis,
a camming recess in the slide portion opening radially of the axis and presenting a camming surface therein,
the casing member having an actuator bore extending transverse to the slide bore from an outer open end into the slide bore,
an actuator member displaceable within the actuator bore between an outer position and an inner position,
the actuator member having a camming protuberance at its inner end for engaging the camming surface,
wherein with the camming protuberance extending into the recess engagement between the camming surface and the camming protrusion prevents withdrawal of the hook member from the casing member and the spring biases the hook member to urge the camming surface into engagement with the camming protuberance which engagement determines the position of the hook member relative the casing member both axially and rotationally;
in moving the actuator member from the outer position towards the inner position, the camming protuberance cams on the camming surface against the bias of the spring to both draw the hook member axially inwardly into the casing member and rotate the hook member relative the casing member.
In another aspect, the present invention provides a releasable joint for modular frame construction comprising a first elongated frame member and a second frame member and a connection device for releasably securing the two frame members together,
the first frame member having a T-shape slot extending longitudinally of the first frame member and defined by a channel opening at an external face of the first frame member of a constant width and by an inner chamber inward of the channel wider than the channel and defining internal chamber shoulder surfaces on each side of the channel,
the second frame member having an external end face with a central slide bore extending into the second frame member open at the end face,
the connection device including a hook member and a spring;
the hook member being elongated about an axis and having a slide portion on an inner end and a hook portion on an outer end, the hook portion having a head at the outer end of the hook member joined by a shank to a remainder of the hook member,
the head as seen in a first longitudinal side view having a first width normal the axis of the hook member which is wider than a width of the shank in the first longitudinal side view so that the head presents head shoulder surfaces directed axially towards the inner end of the hook member,
the head as seen in a second longitudinal side view having a second width normal the axis of the hook member which is less than the first width of the head,
the first longitudinal side view and the second longitudinal side view are disposed relative to each other at a displacement angle about the axis of the hook member as seen in axial end view,
the slide portion of the hook member longitudinally slidably received within the slide bore with the hook member rotatable about its axis relative the second frame member,
the spring coupled between the second frame member and the hook member biasing the hook member longitudinally out of the slide bore and biasing the hook member to rotate in one direction about its axis relative the second frame member,
a camming recess in the slide portion opening radially of the axis and presenting a camming surface therein,
the second frame having an actuator bore extending transverse to the slide bore from an outer open end into the slide bore,
an actuator member displaceable within the actuator bore between an outer position and an inner position,
the actuator member having a camming protuberance at its inner end for engaging the camming surface,
the camming protuberance extending into the recess so that engagement between the camming surface and the camming protrusion prevents withdrawal of the hook member from the casing member and the spring biases the hook member to urge the camming surface into engagement with the camming protuberance which engagement determines the position of the hook member relative the casing member both axially and rotationally;
in moving the actuator member from the outer position towards the inner position, the camming protuberance cams on the camming surface against the bias of the spring to both draw the hook member axially inwardly into the casing member and rotate the hook member relative the casing member through the displacement angle,
the first width of the head being greater than the width of the channel,
the second width of the head being less than the width of the channel,
with the end face of the second frame member engaging the external face of the first frame member with the slide bore centered on the channel in an unlocked position, the actuator is in its outer position and the hook portion is in a rotational position which presents the second width of the head disposed so that the hook portion passes through the channel and the hook portion extends from the slide bore sufficiently that the head shoulder surfaces of the hook portion are in the inner chamber inward of the chamber shoulder surfaces and from which unlocked position on movement of the actuator member to the inner position, the hook portion is rotated through said displacement angle to a position which presents the first width of the head disposed so that the head does not pass through the channel, drawing the hook member axially into the slide bore to engage the head shoulder surfaces with the chamber shoulder surfaces and draw the external face of the first frame member into a frictional engagement with the end face of the second frame member.
The present invention provides a connection device in which a hook member is carried in a casing member for both rotation about an axis of the hook member and movement longitudinally of the hook member inwardly and outwardly relative the casing. An actuating member is provided to displace the hook member simultaneously for rotation and axial movement. The connection device is particularly adapted to be used as an element of a releasable joint for modular frame construction of frame members having T-shaped longitudinally extending slots. With the hook member in an unlocked position, the hook member extends from one frame member carrying the hook member and permits passage into a slot of another frame member. With the hook member in the slot in the unlocked position, the hook member may be moved to a locked position by rotation and withdrawal of the hook member relative the frame member by which it is carried so as to catch the head of the hook member in the T-shaped slot and draw the two frame members together. The hook member in the unlocked position preferably is orientated relative the frame member which carries the hook member in an orientation such that alignment of features of the frame member carrying the hook member with features of the other frame member places the frame members so that the hook member is aligned to be moved into and out of the T-shaped slot.